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镍基催化剂上积碳是甲烷干气重整反应急需解决的关键问题。实验采用ＴＰＳＲ、ＴＰＤ、ＸＰＳ和脉冲反应等方法系统研究了镍基催化剂表面积碳的形态和特点。热力学研究表明，在５７３ Ｋ到１２７３ Ｋ的温度范围内，催化剂的表面积碳是不可避免的。ＴＰＳＲ、ＸＰＳ和ＴＰＤ研究表明，甲烷在催化剂表面裂解将形成至少三种碳物种：Ｃα、Ｃβ和Ｃγ。这三种碳物种具有不同的表面迁移能力、热稳定性和反应活性。其中，Ｃα物种在甲烷干气重整反应中是一种非常活泼和重要的中间体；Ｃγ物种则可能是表面积碳的前驱物：部分脱氢的Ｃβ物种能够与Ｈ２或ＣＯ２反应生成ＣＨ４或ＣＯ。
Nickel-based catalyst for carbon deposition is the critical problem to be solved urgently for methane dry gas reforming reaction. In the experiment, the morphology and characteristics of surface area carbon of Ni-based catalysts were systematically investigated by TPSR, TPD, XPS and pulse reaction. Thermodynamic studies show that the surface carbon deposition of the catalyst is unavoidable in the temperature range of 573 K to 1273 K. TPSR, XPS and TPD studies have shown that methane cracking on the catalyst surface will form at least three carbon species: Cα, Cβ and Cγ. These three carbon species have different surface mobility, thermal stability and reactivity. Among them, Cα species is a very active and important intermediate in dry gas reforming of methane; Cγ species may be a precursor of surface carbon deposition: partially dehydrogenated Cβ species can react with H2 or CO2 to form CH4 or CO .